1. Field of the Invention
This invention relates to a multichannel audio-signal transmission systems, and more particularly to a novel multichannel autio-signal transmission system which is compatible with both of a regular matrix type system and a CD-4 type system.
2. Description of the Prior Art
In the multichannel recording and reproducing, it is known that the quality of reproduced sound field can be enhanced by increasing the number of channels and many 4-channel systems have recently been proposed.
These systems can roughly be classified into a matrix system that informtion of four individual channels is transmitted through two channels after matrix conversion and then reproduced into 4-channel information again and a discrete system that 4-channel information is transmitted through four channels and reproduced. A comparison of the two systems shows that the matrix system is low in reproduced sound image location but simple in construction. While, the discrete system has an advantage that since information of each channel is transmitted independently of that of the other channels, unnecessary information of the other channels does not get mixed in each reproduced information, and hence the feeling of presence is excellent.
At present, records manufactured according to the respective systems and reproducing apparatus designed therefore are on the market. However, since the two systems are not compatible with each other, users are required to get reproducing apparatus designed particularly for program sources of each system, and hence compelled to a heavy disbursement. Further, it is troublesome to selectively employ reproducing apparatus (change over its switch) in accordance with the particular system of a program to be reproduced and this is a cause of arresting popularization of the so-called 4-channel stereo system.